package com.jia.leetCode;

public class Pro0021 {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
    	ListNode dummy = new ListNode(-1);
    	ListNode current = dummy;
        while(l1!=null && l2 != null) {
        	if(l1.val < l2.val) {
        		current.next = l1;
        		l1 = l1.next;
        	}else {
        		current.next = l2;
        		l2 = l2.next;
        	}
        	current = current.next;
        }
        if(l1!=null) current.next = l1;
        if(l2!= null) current.next = l2;
        return dummy.next;
    }
}
